1. Field
Embodiments of the present invention generally relate to a plasma processing apparatus and method of use thereof. Specifically, embodiments of the present invention relate to methods and apparatus for controlling a plasma in a plasma enhanced process chamber.
2. Description of the Related Art
Plasma enhanced processes are often used in semiconductor fabrication, for example, to facilitate the etching or deposition of thin films on a substrate. During such processes, a plasma is generally formed from one or more precursor gases within a process chamber containing a substrate to be processed. The creation and control of the plasma (e.g., plasma parameters such as plasma density, ionization, dissociation, uniformity, and/or the like) is a critical parameter in such processes, affecting such variables as processing rates, processing uniformity, feature critical dimensions, feature profiles, and the like. Many processing apparatus and techniques have been utilized to assist in the control of these plasma parameters to improve process rates, device yield, and the like. However, use of such techniques tend to be a trade-off where improvement of one parameter may be obtained, but at the expense of other parameters. As such, even with the use of such techniques, process improvement continues to be desired in order to further improve process throughput, device yields, overall device quality, and the like, without the negative trade-off often associated with such apparatus or techniques.
Thus, there is a need for plasma processing apparatus and methods for improving plasma control.